1. Technical Field
The present invention relates to a semiconductor device and a method of manufacturing the semiconductor device.
2. Related Art
In the past, for a vertical semiconductor device in which a current is made to flow in the thickness direction of a semiconductor substrate, a configuration of a field stop layer being provided on the back surface side of the semiconductor substrate has been known (for example, see Patent Documents 1 and 2).    Patent Document 1: Japanese Patent Application Publication No. 2009-99705    Patent Document 2: WO 2013/100155
When a field stop layer is shallow, it is difficult to sufficiently suppress turn-off vibration and reverse recovery vibration of a transistor such as an IGBT.